Hi Loic, > IIRC you figured out how to use https://github.com/ceph/ceph-tools/tree/master/models . Do you happen to have some kind of HOWTO or even the list of commands you've used to get me started ? git clone ...ceph-tools cd ceph-tools/models/reliability ./main.py -g At this point a graphical form should pop up and most of it should be straight forward. NRE rate is non recoverable read errors, the NRE model determines how an array/disk responds to a non recoverable read error event. I tend to be on the conservative end having seen my share of RAID horror shows so I set the NRE model to "fail". The other gotcha is most disk manufacturers use MTBF or AFR while the reliability modeling tool requests FITS. The formula you will need is: MTBF = 1,000,000,000 x 1/FIT. [1] Stripe length is the number of RADOS objects that are require to store a blob of data, ie all RADOS objects that compose a RBD volume. Since this code was written a while ago there is no code to support modeling erasure coded objects. If you have any questions, let me know! [1] http://en.wikipedia.org/wiki/Failure_rate#Units -- Kyle Bader - Inktank Senior Solution Architect -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
